Alternating-current signaling apparatus for electric railways.



No. 878,139.' PATENTED FEB. A, 1908.

k F J. s. HOLLIDAY. A ALTERNATING CURRENT SIGNALING APPARATUS FOR ELECTRIC RAILWAYS.

' APPLICATION FILED JUNE 28, 1907.

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a 2:3 I; :5 A E; d I wlfflEssEs 5 INVENTOR 5 PATENTED FEB. 4, 1908.

J. s. HOLLIDAY. ALTERN ATING CURRENT SIGNALING APPARATUS FDR BL ECTRIG RAILWAYS. APPLICATION FILED JUNE 28 1907. V

2 SHEETS-SHEET 2 FIG. 4.

INVENTOF! WITNESSES i at JoI-m s. hominid, oiqvuKiNsBURc, PENNSYLVANIA, Assrcnon TO r'n's i xlo'r ,s vrron' a SIGNAL: court on lENNSXLYANLi.

, Specification of Letters Patent.

O'RSWISSVALE, PENNSYLVANIA, A conronivriox l ALTERNATING-CURRENT SIGNALING APPARATUS FOR ELECTRIC Rl-LI'INV'AYSv Patented. Feb. 4, recs;

-- Application filed June 28,1907. 'Serial No. 381.218.

To all whom it may concern:

Beiit known that 'L-Jonu S. HOLLIDAY, of Wilkinsburg,- Allegheny county, Pennsylvania, haveinvented a new and useful Alternating-Current Signaling Apparatus for .l llectric Railways, of which theiollowing is a lull, clear, and exact description, reference being rad to the accompanying-d rawings, forming part of thiss'pecilication, in which Figures 1, 2,3 and4' are diagrams 1llustrating different forms of my invention.

This invention has relation to signaling systems for electricrailways, Where a single phase alternating current is used for propulsion, and a similar current either of the same or difl'erent' frequency is used for signaling purposes, the object being to provide a system of this character-so arrangedthat the propulsion current cannot operatc'the signals or interfere in any manner with their operation. My invention consists essentially in a rclay devlcefor controlling thes gnals having its winding so constructed and connected as v to be operated, only by the-signaling current, as hereinafter more fully described.

:llel'crring to Fig; l, the numeral? desig natcs track rails, which are divided into insulated sections, as indicated at S. 4 designates inductive bonds'of Well known charactor which connect the track rails at the ends of the blocks or sections. '5 indicates a single phase generator which supplies the conductors 6 from which the currents the track circuits for signaling purposes are su plied or derived. 7 desi nates a single phase generator which supp ied the, conductor 8 from which the cars or other vehicles, one of Which-is indicated diagrammatically 1 at 9, receives the supply of propulsion cur- 40 rent. "10designates a single phase transformer, the terminalsof thepnmary coil of which are connected across the conductors 6.

One terl'ninal of the secondary coil of the transformer is-conne cted' to the two coils or windings 11. and12 of the relay device 1-3 by of the secondary coil. of thetransformer 1O is connected to the opposite track rail'sat the other end of the block from the relay 13,

through the two conductors 14 and 15,- one to go to its danger position.

oitvhieh, as 15 has included therein-a suit- I able inductance 16. Th movable member 13 of the relay is pivoted at 1'7, and operates a switch-contact indicated at 17* which. controls the circuit of the signal 18. The two coils 11 and 12 are displaced with referenceto each other, as indicated, and are eonnect-, ed in parallel in so far as the signaling current derived from the transformer 10 is con cerned, but are in series With each other between the op osite trackrails with respect to any propulsion current whichjinay flow from one'of the rails to the other. ,The' effect of the inductance 16 in the conductor 15 is .to change. thephase relation of the current in the coil 12 with respect to that in the coil 11,

so that said coils act upon the movable 1nem.-. ber13 of the relay in the manner of. a tWo- .70 phase motor. If there is no train in the block, thev relay is suppliedwith this twophase current, andniaintains its closed posi tion,. as shown in the drawings, thereby com pleting the signaling circuit, and holding the signal clear. When a train enters theblook, the two rails are thereby connected, so that the current is transmitted to each of the windings 1 1. and 12 of the relay in the same phase. The two windings therefore exert no action on therelay, and its movable member opens by gravity,.breaking thesignal controlling circuit at] 7 and causing the signal 1 The relay will not be affected by any propulsion current Which may flow through the windings 11 and 12, clue to difi'erences'in potential of the two track rails, since in so fares such current is concerned, the two coils are in series between the track rails, and the current will flow through one coil to its junction with the other coil, and thence back through that coil to the other track rail of the lower potential. Any propulsion current which may i-low through these coils byway of theconductors 14, 15

and 13 is equally ineffective to operate the relay because itfcolnes to both thesewindings throughuthe common- Wire '13: This 'ar i rangeinent 'and connection of the relay coils enables a single phase signaling c1 be-used in the track circuit for signaling" p ur-i poses,-and even though the propulsion cur rent may be of the same frequency, there will be no Interference with, or false operation of;-

50 may be made bythose skilled the art withfrom the spirit and-scope of my invention. hiis any suitable {form of twoxfigure, butto move in either direction under. the action of the two windings 11 and 12.v

skilled the art, since on the two-phase current in the signaling relay,

while the'relay and its'connections may be reduced to a very simple form, 'l he arrangement shown in Fig. 2 is similar to that shown in Fig. 1, with the 'eXception that instead of the transformer 10, an auto=transforiner 10 is employed which is connecteclby a conductor 19 with the conductors 14E and 15 which correspond to the conductors 14 and 15 of Fig. 1, 16 being an inductance which isincluded in the conductor 15 In this form, the connected terminals of the two coils 11 and 12 are connected by a conductor 20 with one of the conductors 6. An advantage'of this arrangement over that shown in Fig. 1 is that it dispenses with the conductor 13* of Fig. 1 leading back from the relay to the transformer at the other end of the block.

In the arrangement shown in Fig. 3, a polarized or vreversing relay is employed for controlling the two sets of contacts 2land 22. In this form-of relay, the movable contactcarrying member 23 is pivoted at 24, so asto assume the normal position shown in the Theselwindings together with the general arrangement of the circuits therefore are the same as those shown in Fig. 1, excp th l' reversing switch '25 is inc uded in the con-j;

ductors 14 and 15, whereby. the inductance 16 can be connected inse'ries with-either winding 11 or 12, the direction of movement of theyrelay depending. uponp'which winding the inductance is connected in .series with.

The arrangement shown in Fig. 4 is si'milai'to' that shown-in Fig. 3, except that an auto transformer similar to that of'Fig. 2' is used.- The advantage of the reversing relay shown in'Figs.'.3 and/1 will beaplparent'to, tlfiose ytwo or t ree transmissionline's' or mains are required for its operation. I 1

It 11 be obvious that various changes out dep arti phase motor for operating. the i'eliiy may be used, as the arrangement and' lcoi'nbination of the parts may be changed. 1

What I claimis 1-.

f1. Inan alternating current system for electric railwa s using alternating" current.

for both signa ing and propulsion 'purpgses,

a relay having two windings, and circuit1 con= nections therefor whereby the phase. ot the signaling current passing-throw. h saidWindings is split, 'while the-phaseo asgpmsui- 6.- In an alt'ernat" not changed; substantially as described.

2. In ansalternating current system for electric railways using alternating current 'sion current which-may pass therethrough is e5 for both signaling and propulsion purposes, a

relay having two windings which are in series with each other with respect to propulsion current which may flow from one rail to the other, and in parallel with respect to the signaling' current, and means in series with one' of said windings for changing the phase of the signaling current passing therethrough; sub-- stantially as described.

3. In an alternating current system for electric railways using alternating current for both signaling and propulsion purposes, a rela having two displaced windings connecte in series across the track and in parallel with respect to the signaling current, and means for changing the phase of the signalin current in the two windings; substantially asdescribed.

'4. ,In an electric railway system using a single phase propulsion circuit, and a single phasesignaling circuit, sectional rails, a relay aving two sets of windings, means whereby the phase of the signaling circuit passing through said windings is normally displaced,

while-the phasef 'of .any propulsion current -passing -.thereth i:engh is not changed, said windings be'iri'g sh'connected that the presence of a-trainin the section put the currents in said 'windingsin phase with each other;

substantially as described.

.- 5, 'In, anfalte'i'nat' current system for electriciailways, a're ay having a contact- ;operating member movable in both direc- 'tIOD S fIOmIQFCQDtIBIl position, 'twoisets of windings arrajn ed toact on said member, an i inductance, an means for connecting thetin-"- ductance inseries with either one of said windings; substantially, as; described.

current system for electric railways 'areaysliaving a contact- I operating member movable .in bothdirec tions from a central? position, two sets of 'windin s arranged to act voil-said.member, means, or'dis l'acingthe'phase'inone of said windingg'an means for "eluding'the hase displacing means inseries with either 0 said .winding'sf; -substantially as described. l

'. 7.. In-an alternatingeurrentsystemgformission linesor mains lea .therefiom, sectional track rails, apolarize or revers n relay having two windings connected to 'sai rails and to f the transmission lines, and means for displacing the current base-in electric railways, ;a single ;-phase generator for supplying signaling current, two trans- In testimony whereof, I have hereunto set my hand.

single phase generator, two transmission lines leading therefrom, a plurality of Windings for actuating the relay and connected to the transmission lines, and means for dis- 5 placing the phase in said windings to actuate Witnesses:

said memberin either direction; substantiall i JENNIE E. Slurp, I as described. I JAMEs'A. \Ylurms.

JOHN S. HOLLHLRI. 

